Principal Engineer - Cards API's

Worker Type:

Permanent

Here at BNZ, it's about more than just banking. We work together in an agile, energising environment to create innovative solutions through our promise "If you can imagine a better future, let's find a way."

We support wellbeing, flexible working and have a generous leave offering. There is the opportunity for growth, learning and career development. No two days are the same.

We have an exciting opportunity for a Principal Engineer to join our Cards & Merchants team and lead the technical direction of our API and integration estate, directly improving resilience, reliability, and customer outcomes for years to come.

Mō te Tūranga | About the Role

We sat down with our Platform Manager, and they let us know the following about the role.

What are 5 day-to-day tasks the person in this role will complete?

• Lead technical decision-making across the API estate: Facilitate architecture discussions for our Cards and Merchant APIs, evaluate integration trade-offs, and guide teams toward scalable, standards-based, and reusable API solutions.

• Drive API quality and risk-reduction initiatives: Review API contracts, specifications, and event schemas for reliability, security, and testability. Identify systemic risks across the integration landscape and embed “quality by design” practices for enterprise interfaces.

• Mentor and support API engineers: Coach senior and emerging engineers on API design, integration patterns, and enterprise interface standards. Provide feedback on API contracts, event-driven designs, testing strategies, and technical growth plans.

• Solve complex technical problems: Ensure the team is ready to identify and resolve issues across our API and integration platforms. Investigate root cause and model structured problem-solving to help the team converge on scalable, enterprise-grade solutions.

• Collaborate and influence across the organisation: Work with Platform Owners, architecture, product, engineering, and leadership stakeholders working across BNZ Technology to align on API priorities. Partner closely with the Architecture team to ensure API and integration designs align with enterprise architecture standards and target-state roadmaps. Communicate technical direction clearly and challenge assumptions constructively.

What is the team culture and environment like?

Across the BNZ we’re a collaborative bunch who value open, honest conversations and continuous improvement. Everyone’s got a strong sense of ownership over the customer experience - from keeping things running smoothly to finding ways to make them even better. We’re big on learning, sharing what we know, and staying curious.

What is the most exciting thing about this opportunity?

There is a need for us to uplift our API capability across Cards & Merchants, which creates a large opportunity to shape the architecture, patterns, and engineering practices that define reusable, standardised APIs and reliable enterprise integration for years to come. You’ll sit at the centre of a busy, high-impact programme of work spanning Cards, Merchant, and enterprise interface services, with plenty of momentum and the ability to reduce fragmented integration and duplicated effort across the domain.

What is the most challenging thing about this opportunity?

This role offers the chance to drive the development of robust, scalable API solutions that deliver sustainable business outcomes, while balancing significant system dependencies across multiple interconnected domains. You’ll need to bring order and standardisation to a fast-growing integration estate while supporting live delivery.

What technical skills are required for this role?

This is an opportunity to bring your proven API and integration architecture experience, including strong hands-on expertise designing, securing, and scaling enterprise interfaces. Experience within a banking or financial services environment is desirable. We are also looking for experience in:

• Core Development: Strong hands-on experience with Java and Spring Boot/Spring for building enterprise-grade API and integration services.

• API Design & Gateway: Experience designing and reviewing RESTful APIs, including API contracts, specifications, request/response payloads, data mapping, authentication, and error handling, secured via Kong (REST, JWT). True end-to-end delivery always goes through Kong, so a solid understanding of gateway-based integration is essential.

• Build & Container Platform: Proficient with Gradle for build management and Docker for containerisation, with services deployed and run on Openshift and EKS (Kubernetes).

• CI/CD & Delivery Tooling: Familiarity with the bank’s standard pipelines: Bitbucket for source control, Jenkins for build, and Spinnaker for deployment.

• Secrets Management: Experience using HashiCorp Vault for secure storage and management of API keys, passwords, and other secrets.

• Messaging & Data: Depending on requirements: IBM MQ (JSON over MQ) and/or Kafka for messaging and event-driven integration, and PostgreSQL (Aurora) for data persistence.

• Testing: Experience with JUnit, REST Assured, and TestNG for unit and API/integration testing, with true end-to-end test coverage validated through Kong.

• Tooling: Comfortable working in a modern Jave IDE

• Domain Knowledge: An understanding of cards and card/merchant data flows would be beneficial.

What attributes will this person display in order to be successful in this role?

• Strategic, Systems-Level Thinking: You have the ability to see the bigger picture and design for a long-term, reusable API estate, while understanding how integration decisions impact business outcomes.

• Technical Mastery and Curiosity: Alongside your deep expertise in API design, architecture, and platform integration, you will act as a guardian of technical excellence and engineering culture across the domain.

• Problem-Solving Under Ambiguity: You’ll have the ability to thrive in unclear or systemic integration problems and use structured thinking to identify root causes and guide teams toward scalable solutions.

• Quality and Risk Mindset: You naturally design for reliability, security, and testability across every API and integration point, spotting risks early.

• Mentorship and Leadership Maturity: Grows others through coaching, feedback, and modelling good API design and engineering behaviours, while helping create an inclusive, learning-focused environment.

• Strong Communication: Clearly conveys technical direction to both technical and non-technical stakeholders across multiple interdependent domains.

• Ownership and Accountability: You’ll be able to take responsibility for outcomes and move API and integration initiatives forward even when obstacles appear.

Nau Mai ki te Pēke o Aotearoa | Come to the Bank of New Zealand

Please note applications close Friday 16 October 2026.

This is an exciting opportunity to join us!  We're bold thinkers who are taking brave steps to create a company that people want to work for, and customers want to bank with. If you're ready to join a fun organisation where we are proud of our culture and how we are helping New Zealander's to 'Find their way', then show your interest by submitting your application - we can't wait to read it. 

Ehara taku toa i te toa takitahi, engari he toa takitini" - Success is not the work of an individual, but the work of many.”

Closing Date: 16 October 2026

Applications will be reviewed regularly across the advertising period, but we do reserve the right to close applications early.